The US Centres for Disease Control and Prevention (CDC) issued new guidelines on Friday, saying people who have had close contacts with somebody with a corona-virus infection need a test, even if they do not have symptoms.
The change came after a controversy in late August, when the agency suggested those people did not need Covid-19 screenings.
People who do not have symptoms and are not close contacts of an infected person still do not need a screening, unless it's recommended by a medical provider or public health official, according to the latest CDC statement.
The August shift on testing asymptomatic individuals had said testing might not be needed for asymptomatic close contacts. It was slammed by public health experts, who said it could reduce the amount of testing performed in the US.
Mr Brett Giroir, a top Trump administration official overseeing the testing, defended the change in a briefing the previous month as intended to illustrate the limitations of the virus screenings and said the new guidelines were "a CDC action".
But the New York Times reported on Thursday the guidelines were rewritten by the Department of Health and Human Services (HHS) and released in spite of CDC scientists' opposition. The testing guidelines released on Friday were changed by HHS and did not go through the CDC's typical review, according to the Times report.
HHS and CDC did not immediately return requests for comment.
Public health experts have advocated mass testing as a means of identifying virus cases and preventing further spread, but the US has yet to achieve a system of widespread, easy-to-access, quick-turnaround screenings. While availability of testing for people with symptoms has improved significantly over the course of the pandemic, those without symptoms can still face barriers.
Experts are worried the CDC guidance, which applied to both asymptomatic close contacts as well as those who attended large, risky gatherings but had no symptoms, would exacerbate those challenges.
According to the new recommendations, those who are in an area of high virus transmission and go to a large gathering with spotty public health precautions may be advised to get a Covid-19 test by their doctor or a public health official.
BLOOMBERG